Hack saw machine



July 10, 1934. c. FLETCHER HACK SAW MACHINE Filed Sept. 8, 1930 4 Sheets-Sheet l y 10, 1934- c. FLETCHER 4 HACK SAW MACHINE Filed Sept. 8, 1930 4 Sheets-Sheet 2 Ja ha Qz70mzg.-WMw

HACK SAW MACHINE Filed Sept, 8, 1930 4 Sheets-Sheet 3 Ewan/07: flaw; 1M4.

July 10, 1934.

c. FLETCHER 1,965,743 HACK SAW MACHINE Filed Sept. 8, 1930 4 Sheets-Sheet 4 Patented July 10, 1 934 Se'dgleyfFletchei', CharlesNon-m'dnIletcher;and

Sz'adgle'y-Bernice Fletcher,--eigecutofs fqfsum "CharlesFletchiy'fdeceased -TM FHY QQQ VIQ FS,'99 he k-sa zne hine Me a sawin .me ;h ne er .ve fi liy ndifi u are imaei an imm e ies vi" .rhack e' w leeeeh e QQwin ye' 'iml e 5 pro ents and developments the latest nodels i ircula r sa m esl ere how oepa hle of jpjroyed output cepacity and efiic'iency'. 45 A cor n wim i aw or the invention the saw is rigidly 's'eciiied eltits ends in a: fi'ani'; Withegt tension and, is "sufipor'ted. inteifrriediajtelybf its Acconding to anotherfeeture of the invention th e wma t eb iltui gth t s'a gcd iprfs- L f 'ing"in'cof1nbifr 1:ationla, bladetof for dinfirfi vvidthand ,a supporting incite; 'which' 'suiipo ting 'fplait'e may ealsofiiiovide latefaliigiditYfOithe bla'd', Iajnd injsertefdfteethfrnady Joeused in the saw. Another .4 25 feature ofl'tne" invention;- 151 to tonsilan ne jfi a'ine sothtt itfin'ai form "a clamp tfonith'ese'vv. Th i n e ti a cq' ri l i ck "r6? the fe' d "mechanism endflift fnotion t r the sawin operation. W e0 p'q fth@QQmP nYin flmW n I Figs.;1 1; nd:1dcon tute 9, side elevhtion of one exanipl o f 'hl'cki Sgt emneeinbqqymg the sex;- erarife pu theinv'ent'ionl" ,FigIZ is afront'ele'vation of pa tof the machine Ji 'amlfi h wtde i iofpn fin i-ihe S w blade fo'LiIa: r a' le': 3 rAsi l fi tedx heim o e c aiwlma h which is the sawin'gtable 'Zjgnd vi s .ing the woi k on each side ofjthe Qoneonly of such. vices being shown 1' ,45fliiig sffAtlthe backjend' of ithe table's,

crenk -ofethecrenlgshaft d. At theif'up'pe'i ends thlinks' y'hi'e mounted on the eccentric ends of a, spindle e journaled in the arm e and connected by links 6 and e to the rear end of the saw arm .60 e. A link 6 is connected to the common pivot of the links e and e cand toithe lug h on the connectingjodihl" eccentric for lifting'the'saw e' 'i'nlmzty' b arrngefd at-"the' other end of'jthe linksll, Q with silltblemodified actuating mechanism. The'pi'vots'lfofthe"aimeniay be concentr'ic vvit hithe bearings; of thecrank-shaft, or above the'ciank shaift ilhi'stfatedso'as to enable'the yvid'th 'of thejniachine 'm'bac'k to front to be as small as possiblffflh ,arme is of U shaped cross s'ectioflhaving'fiwolongitudinal webs 42 one at 'eechsideQ of irafyin'g depthjwhich extend at the iealr end to' forni' fii'votjlug s. M on the 'ilnderside of fa'i' n .ai fiebending extensions 6' to which ,eieilooltedheteining 'slid'sc foi the saw frame. The sewfianie ",f, Whicli'i is connected by' the connecting rod ch to thecfank of the crank-shaft 'd, emfi nses'a sude'pamhavmg on its upper side tv'iov' sh'aped'slide portions f toengage the correspondingslide grooves e fthioiigh which slide l jrtldfis thpressure is applied to the saw for the ciitj On'theiinderside; along-each edge, the js'l ide, has" ttvo fiatfslid surfaces engaging the reaining slide: plates e end' on which the saw jrrame is lifted 'with' the arm; To the underside of this slide part are bolted two arms Eff-long Q5 flangesii betweenvvhich the saw f is to be sec edfwhichflfmsafe' arched to" expose the fentreonvvorkin portion of the saw. The ends of wearin fineiy'fb'est'rengthened by flanges i twhieh wur merge intditlie lipp'er' flange 1 I The ,99

Ii edg the salwj lies igztinstj the slide part "so that itfis'gdireotlysupported thereby for the f fwholeof its length;andfdf'claznbing the sa bejvtvveeriwthe arl'nsj boltsj'are provided in' th alrms fer t e frame y the two" ems caii 'be ,gs cnizr ed together to'gripthe saw. 1 The cla'i'mping bolts preferably: pass through the saw sothet it v ,ibQjIfid; tbithe' "fialiie fiA clamping screw" k is fo o 'p'iovided' ce'ntr'allly in 'thllp'nef flanges Ti Brackets" jfiifoi" i' pi'vo't pin for the connecting 170d E are c d"tofthefaffiiiges'oftheflame 5b bolts esjs hown; or these may be cast nnne lqeiwi hjhejframe.

'th njthe ibaseof the machine is the feed mechanism comprising carriage ficarryingh 195 ii tfifibhnted oriiajf'eed screw 11. and guide we f1}? onebnly'of which is shown. Ih d riving mech- 'f which be :firdvided '88 all indfiena'eht nnit fitted" 'nto thebasefcompifis'esh vertical coi nter s "o behindflthe feed scfew n geared 1:10 thereto gitfj its; lo r? end by pinionsfokj b and Bi'ovideci" with? afbevel' wheel 0 at its 'upber'end. LA f d f Zfii a i I diilt i gfi 1 "1 ?i i 't jo il rnild in the *friifibf the feed u'iiit arlqna'vi a beve whe p1 ut le vwi j hefb 1 4 1 *1 w *vi ti'cahshaft. On the 'efidpf IiGifiOh B t :1 i '3 i 1 'l' adaiitewto engagehltem tivelywithhoilnterpzirt clutches journaled on the shaft, the inner one of which is adapted to be driven at a relatively high through a counter-shaft q so as to provide a quick return or lift for the saw. The outer clutch counter-part is driven by pawl mechanism from the crank-shaft d, the circumference of the clutch being provided with ratchet teeth s. The pawl mechanism comprises an arm s rotatably journaled on the end of the horizontal shaft, carrying a pawl the outer end of the arm being connected to one end of a link 8 In place of the toothed ratchet the known friction band type of ratchet may be used which will obviously give intermediate rates of feed and is quieter. The other end of the link s is connected to a pivot s on a slide block 8. adjustably positioned in a diametrical slot in a wheel 8 fixed on the end of the crank-shaft d. The throw of the pawl mechanism is'therefore adjustable by adjustment of the position of the slide block s in its slot. Over the sliding clutch is arranged an operating fork it having a short arm t extendfrom the pivot towards'the base of the machine. In the end of such arm is positioned a plunger t with Wedge-shaped outer end, and behind which is positioned a short compression spring t Immediately opposite to such plunger is a similar shaped stud u in the end of 'a lever u pivoted in a bracket, and connected at its other end to a rod u the other end of the rod being connected by a knuckle joint to a further rod a passing through alug u on the side of the saw arm, and provided with adjustable stops 11. to engage such lug.

The arm t which controls the clutch for the lift or feed of the saw arm, is connected to catch mechanism which releases the belt striking gear and so stops the machine entirely at the moment the saw arm has been lifted to the predetermined distance. ,1

This catch mechanism (see Fig, 3) comprises a sliding bar 12 carrying the belt changing forks 11 and mounted on a guide rod 22 supported by brackets 12 secured to' the base a. A spring '0 is provided on the rod 0 to return the bar to the off position and carry the driving belt on to the loose pulley 1 One of the brackets v 'extends beyond the base. formed a wedge-shaped catch piece '0 The brackets themselves are also'formed to support the sliding bar '0 horizontally above its guide rod 21 Formed on the sliding bar 12 is a stop lug v overhanging the side of the bar, and pivoted to the bar is a cranked trip lever 0 one end of which engages beneath the lug 12?. The other and depending end of the cranked trip lever is slotted 1 and is engaged by a pin 11 on one arm of the starting lever '0 Above the sliding ,bar 1) is pivoted a catch 11 adapted to engage the catch piece 0 and having an extension 12 adapted to .be engaged by the end of the trip lever 12 Pivoted on the frame is a combined catch and trip lever 11 adapted to engage and lift the catch portion of the catch 12 and also to :engage behind the catch v 12 has lifted the catch 0 the bar 12 moves slightly until caught by the end of .the lever v engaging the catch piece '0 so that the catch 11 cannot re-engage when theend of the lever 12 is 1 withdrawn.

H In operation,by depressing the starting handle thebar v is caused to slide and by its belt changingforks 0 starts the machine. When the bar I On the side of the bar 1) is When the lever the ratchet feed mechanism is in operation.

When the saw reaches the bottom of its out, the rod 11. is depressed by the engagement of the lug it against the lower adjustable stop u thereon. The downward movement of the rod a depresses the lever u and presses back the plunger t against its spring 5. This movement continues until the stud u on the end of the lever u passes over the end of the plunger 15 when, by reason of the spring t the plunger t slides up the upper face of the stud u and causes the operating fork t to move across to engage the saw lifting drive. With such action the lever vi is moved so as to trip the catch lever 12 and its spring 12 returns the belt fork to the o position and all the parts are again in the position shown in Fig. 3. The catch 12 may be released by means of the handle 11 by raising the latter, the initial movement of which causes the trip lever 22 to depress the end 12 of the lever 0 On the end of the crank-shaft d is a gear wheel d meshing with a gear wheel (1 on the shaft q on the end of which shaft is also a gear wheel d meshing with a gear wheel d on the driving and loose pulleys r and 1' respectively. A pump 1 for the cutting lubricant is provided in the base of the machine, and isdriven by a suitable belt r from the main driving shaft 1.

shaft 1' on which latter shaft are provided fast In a modification, the saw frame arm may be supported on a slide, instead of being pivoted and the saw may be vertical instead of horizontal.

The machine will preferably be made with the base in one casting so as to obtain rigidity.

The divided construction of the saw frame 1.

allows thesaw f to be insertedfrom the end or from one side and its rigid construction and the secure fastening of the saw render it so much a part of the frame as to allow of heavy pressures and work withoutspring or vibration.

Figs. 4 and'5 show the saw as fitted in the machine shown in Figs. 1, 1a and 2.

What I claim is:- v 1. In a hack saw machine, a screw feed and lifting mechanism for the saw, comprising connecting links between the saw frame andthe screwfeed mechanism and an eccentric forming one pivot of the links, as set forth.

2. In a hack saw machine, a screw feed and lifting mechanism for the saw comprising connecting links between the saw frame and the screw feed mechanism, an eccentric forming one pivot of the links a crank shaft and connecting rod for driving the saw frame and link mechanism connecting the eccentric to the said crank,

as set forth.

' CHAS. FLETCHER. 

